The paper investigates the role of the critique of the Ramist model for the norms of each science in the emergence of the concept of philosophy as the system of all sciences at the turn of the seventeenth century. By focusing on the conditions put forth by Bartholomäus Keckermann for characterizing philosophy as a system of systems, it shows that the legacy of Aristotle’s Analytica posteriora was part of the Ramist precepts and of Keckermann’s systematic approach to philosophical disciplines in two different ways. This difference, it is argued, made an essential impact regarding the functions granted respectively to logic (Ramus) and to metaphysics (Keckermann) in understanding the architecture of knowledge.